<template>
<div class="app-container">

<h2 style="text-align: center;">发布新课程</h2>
<el-steps :active="1" process-status="wait" align-center style="margin-bottom: 40px;">
<el-step title="填写课程基本信息"/>
<el-step title="创建课程大纲"/>
<el-step title="提交审核"/>
</el-steps>

 <el-form label-width="120px">
        <!-- 课程标题 -->
        <el-form-item label="课程标题">
            <el-input v-model="courseInfo.title" placeholder=" 示例：机器学习项目课：从基础到搭建项目视频课程。专业名称注意大小写"/>
        </el-form-item>

        <!-- 所属分类 TODO -->
        <el-form-item label="课程类别">
             <!-- 一级 -->
        <el-select
        v-model="courseInfo.subjectParentId"
        placeholder="一级分类" @change="subjectLevelOneChanged">
            <el-option
                v-for="subject in subjectOneList"
                :key="subject.id"
                :label="subject.title"
                :value="subject.id"/>
            </el-select>
        <!-- 二级 -->
        <el-select
        v-model="courseInfo.subjectId"
        placeholder="二级分类">
            <el-option
                v-for="subject in subjectTwoList"
                :key="subject.id"
                :label="subject.title"
                :value="subject.id"/>
            </el-select>
     </el-form-item>

            <!-- 课程讲师 TODO -->
        <!-- 所属分类：级联下拉列表 -->
    <!-- 一级分类 -->
        <el-form-item label="课程讲师">
            <el-select
            v-model="courseInfo.teacherId"
            placeholder="请选择">
                <el-option
                    v-for="teacher in teacherList"
                    :key="teacher.id"
                    :label="teacher.name"
                    :value="teacher.id"/>
                </el-select>
        </el-form-item>

        <!-- 总课时 -->
        <el-form-item label="总课时">
            <el-input-number :min="0" v-model="courseInfo.lessonNum" controls-position="right" placeholder="请填写课程的总课时数"/>
        </el-form-item>

       <!-- 课程简介-->

        <el-form-item label="课程简介">
            <tinymce :height="300" v-model="courseInfo.description"/>
        </el-form-item>

        <!-- 课程封面 TODO -->
        <el-form-item label="课程封面">
           <el-upload
                :show-file-list="true"
                :on-success="handleAvatarSuccess"
                :before-upload="beforeAvatarUpload"
                :action="BASE_API+'/eduoss/fileoss/upload?host=cover'"
                class="avatar-uploader">
                <img :src="courseInfo.cover">
            </el-upload>
        </el-form-item>     

        <!-- 课程价格 -->
        <el-form-item label="课程价格">
            <el-input-number :min="0" v-model="courseInfo.price" controls-position="right" placeholder="免费课程请设置为0元"/> 元
        </el-form-item>

        <!-- 保存 -->
        <el-form-item>
            <el-button :disabled="saveBtnDisabled" type="primary" @click="saveUpdate">保存并下一步</el-button>
        </el-form-item>
</el-form>

</div>
</template>

<script>
import course from '@/api/edu/course'
import subject from '@/api/edu/subject'
import Tinymce from '@/components/Tinymce'

export default {
    //声明组件
    components:{ Tinymce },

    data(){
        return{
            saveBtnDisabled : false,
            courseInfo:{
                title: '',
                subjectId: '',
                subjectParentId:'',
                teacherId: '',
                lessonNum: 0,
                description: '',
                cover: '/static/01.jpg',
                price: 0 , 
                url:''
            },
            courseId:'',
            teacherList:[], //所有老师
            subjectOneList:[],//课程目录一级
            subjectTwoList:[],   //课程目录 二级
            BASE_API: process.env.BASE_API // 接口API地址

        }

    },
    created(){
        //获取路由id
        if(this.$route.params && this.$route.params.id){
                this.courseId=this.$route.params.id
                //调用查询课程信息
                this.getCourseInfo()
        }else{
              //初始化所有讲师
            this.getListTeacher()
            //获取一级科目
            this.getOneSubject()
 
        }
        // this.subjectLevelOneChanged()
        // this.handleAvatarSuccess()
        // this.beforeAvatarUpload()
    },
    methods:{

        //根据课程id查询课程信息
        getCourseInfo(){
          course.getCourseById(this.courseId)
            .then(respose =>{
                //在courseinfo有课程基本信息
               this.courseInfo= respose.data.course
               //查询出所有分类 。1级和2级
                subject.getSubjectTree()
                .then(respose =>{
                        //获取一级分类
                       this.subjectOneList= respose.data.tree
                        //比较courseinfo里一级id 和 所有一级分类id
                       for(var i =0;i < this.subjectOneList.length;i++){
                            //获取每个一级分类id
                                var subjectOne=this.subjectOneList[i];
                                if(this.courseInfo.subjectParentId===subjectOne.id){
                                        this.subjectTwoList= subjectOne.children
                                }
                       }

                })
                this.getListTeacher();
            })

        },


       //上传成功
        handleAvatarSuccess(res,file){
             this.courseInfo.cover =res.data.url
        },
        //上传之前
        beforeAvatarUpload(file){
            const isJPG = file.type === 'image/jpeg'
            const isLt2M = file.size / 1024 / 1024 < 2

            if(!isJPG){
                this.$message.error('上传图片只能是jpeg格式');
            }

            if(!isLt2M){    
                this.$message.error('上传头像图片大小不能超过2MB!');
            }
            return isJPG && isLt2M

        },

        //一级二级联动 value=一级id参数值
        subjectLevelOneChanged(value){
          
            for(let i=0; i<this.subjectOneList.length; i++){
                    if(this.subjectOneList[i].id===value){
                        this.subjectTwoList=this.subjectOneList[i].children
                        this.courseInfo.subjectId = ''
                        
                    }
            }

        },
        //查询所有一级分类  
        getOneSubject(){
            subject.getSubjectTree()
            .then(respose =>{
                this.subjectOneList=respose.data.tree
            })

        },
        

        //查询所有讲师
        getListTeacher(){
            course.getTeacherList()
            .then(respose => {
               this.teacherList = respose.data.items
            })
            
        },

        //添加课程
        addCourse(){
            course.addCourseInfo(this.courseInfo)
            .then(respose =>{
                //提示信息
                this.$message({
                    type:'success',
                    message:'添加课程信息成功！'
                })
            //跳转到第二部
            this.$router.push({path:'/course/chapter/'+respose.data.courseId})
            })

        },

        //修改课程
        updateCourse(){
            console.log("------------>"+this.courseInfo)
            course.updateCourseInfo(this.courseInfo)
            .then(respose =>{
                //提示信息
                this.$message({
                    type:'success',
                    message:'修改课程信息成功！'
                });
                //跳转到第二部
            this.$router.push({path:'/course/chapter/'+this.courseId})
            })

        },

        //判断 添加还是修改
        saveUpdate(){
            if(!this.courseInfo.id){
                   this.addCourse()
            }else{
                this.updateCourse()
            }

            
        },

        //初始化
         init(){
             //判断路径中是否有id值
        if(this.$route.params && this.$route.params.id){
            //从路径获取id值
            const id = this.$route.params.id
             
        }else{

            this.courseInfo={}
        }

         }
        
    },
   //  监听
    watch:{
        $route(to,from){ //监听 路由变化，执行 清空表单方法 
            console.log('watch $route')
            this.init()
        }   
    }
}

</script>


            <style scoped>
                .tinymce-container {
                      line-height: 29px;
                }
            </style>